3993275825domain: NAppears in sequencesE.g.f. C(x) satisfies: C(x) = cosh( Integral C(x)^4 dx ).at n=6A281428E.g.f.: C(x) + S(x) = exp( Integral C(x)^4 dx ) where C(x) and S(x) is described by A281428 and A281427, respectively.at n=12A281429